Thousands gather for Texas plant explosion memorial

President Barack Obama speaking at the memorial service for those lost in the West, TX fertilizer plant explosion. (Source: CNN)

Workers and investigators take a moment of silence for the lives lost after the plant explosion. (Source: CNN)

A row of 12 coffins, each draped with a flag honoring the lives lost during the West, TX plant explosion. (Source: CNN)

WACO, TX (RNN) - President Barack Obama offered words of encouragement at a memorial service Thursday for victims of last week's fertilizer plant explosion in the town of West, TX.

Obama told the crowd no words adequately describe the courage displayed by those who died.

"What I can do is offer the love and support and prayers of the nation," he said. "We need people who so love their neighbors as themselves that people are willing to lay down their lives for them. America needs towns like West."

Fourteen people died from an explosion at the West Fertilizer plant, which leveled the small town of West on April 17. Hundreds of others were injured.

"First-responders know better than anyone that there's no such thing as a routine emergency," Texas Gov. Rick Perry said. "But it didn't slow them down as they raced toward that burning factory."

According to the Associated Press, about 10,000 people attended the memorial, including 4,000 first responders from around the country. A procession of 300 firetrucks happened before they service.

Family members were escorted into the ceremony on the Baylor University campus in Waco. In front were 12 flag-draped caskets. Large pictures of each victim were placed in front them.

"Today we honor the lives of 12 great men who gave their lives in an enduring act of love," U.S. Senator John Cornyn said.

Video messages from family members were played during the service.

The service was a show of strength, solidarity and resolve.

"The ground shook in West, collapsed buildings and broke hearts, but it couldn't break this community," said Chief Ronald J. Siarnicki of the National Fallen Firefighters Foundation.

The honor guards and firefighters from across the country attended the memorial service for the responders killed.

"It's important to remember that public safety is a dangerous job and everyday firefighters, police officers, EMTs die and we feel it's important to honor their sacrifice and their commitment to their community and to their country," Eric Whiteman with Travis County EMS said. "That's why we have the honor guards is to remember times like this when members of department have passed away or other departments we can honor their sacrifice."

According to CNN, city workers from Waco will replace West workers so they can attend funerals and take a break from trying to repair the city's water system and cleaning up the town.

The explosion left nearly a 100 foot wide and 10 foot deep crater where the plant once stood. The blast also destroyed dozens of homes and damaged several buildings.

Federal and state investigators are still trying to determine what caused the fire that set off the explosion, but have ruled out natural causes.

"There's no theories or range for what ideas caused this fire. There's many, many out there. And, I'm not going to go into specifics for sensitivity reasons at this point but, I can tell you there are a lot of things we're looking for at this point," State Fire Marshal Kelly Kistner said.

After being forced to evacuate their homes, then asked to stay away for safety concerns and a continuing investigation, the first wave of West residents were allowed to return to their homes Saturday.

Obama has ordered that the U.S. flag at federal buildings and military facilities in Texas be flown at half-staff Thursday in memory of the victims.

Obama was already scheduled to be in Texas Thursday. He attended a dedication ceremony for President George W. Bush's library.

A White House official said the Obamas would meet privately with the families after the service.